Fatigue Analysis of Spike Segment of Special Tractor Wheels in Terms of Design Improvement for Chernozem Soil

The driving wheels affect the tractive efficiency, fuel consumption, and soil compaction. This study presents the fatigue analysis of a spike segment that is the main part of an innovative driving wheels designed to improve tractor tractive performance. The design improvement was proposed for Chernozem soil allowing the full penetration of spikes. The spike segment was loaded by forces resulting from the maximum drawbar pull at 100% wheel slip and penetrometer resistance. A drawbar pull increase caused by the spike tires was also calculated. The experiments were performed using a subcompact tractor in the first gear on a grass field at soil moisture 18.8%. Gerber theory was used for the fatigue analysis performed using ANSYS software. The dependances of the safety factor on the horizontal rod diameter and the number of load cycles was constructed. The safety factor of 1.73 calculated for the spike segment made of steel S355 is suitable for the reduction of the actual horizontal rod diameter (12 mm). The fatigue analysis showed a safety factor of 1.28 at 100,000 load cycles in the case of a reduced diameter (10 mm). A diameter of 8 mm was also simulated, but the calculated safety factors do not allow it in terms of safe operation.